Process of mercerizing



Patented May 5, 1936. I

UNITED STATES masses ,or irsnonarzmd Donald 1!. Powers, Moorestown, N. 1;, and Louis Bock, Bristol, Pa., assignors tollilnna HaasCompany, Philadelphia, Pa.

No Drawing. Application July 3, 1933,

Serial 5 Claims. (CL 8-20) This invention comprises improvements in and relates to the treatment of cellulose or celluloselike bodies with compounds possessing a swelling or dispersing action.

It is the object ,of this invention to effect the mercerization of cellulose materials to give products of high luster and strength. It is a further object of this invention to carry out the swellin or mercerization of cellulose over a wide range of temperature. It is a further object of this invention to accelerate and activate the mercerlzing effect of inorganic hydroxides.

It has long been known that aqueous solutionsof alkali and of many organic bases possess a swelling action for cellulose. Sodium hydroxide has long been used as a mercerizing agent due to the faet that it possesses a swelling action on-cellulose producing a fiber with increased luster and strength. It is shown by Knecht and Harrison compounds which effect a swelling of cellulose and those compounds which actually dissolve this ma-' terial to form aqueous solutions or dispersions of cellulose with'a concentration of 3 to 15%.

30 Schwalbe 8: Rbbinofl (Z. angew. Chem 24.

(1911) 256258) showed that pure cotton had asolubility of 0.06% m 8% caustic. They also show that the more degraded the cotton the higher the solubility. In general, however, cellulose is'not considered soluble in sodium hydroxide and the repeated processing of cellulose materials and fabrics in alkali solutions of widely varying concentrations has confirmed this. It is well known that cotton piece goods are boiled under pressure with 3% caustic for to 40 hours without harm-. ing the cellulose, purely for the removal of the extraneous gums and waxes.

The degree of mercerization is frequently used as the measure of the swelling of cellulosic materials and we find that organic bases vary widely in their apparent swelling and value as mercerizing agents. For example, a solution of tetramethylammonium hydroxide with a concentration of under carefully controlled conditions, appears to give a mercerization comparable with I that obtained with sodium hydroxide and yields an' increase of strength of 15 to 18%. Solutions of higher concentration of this hydroxide cannot be readily prepared, as-its hydrate crystallizes from aqueous alumn e-Aqueous solutions of (Journal of the Society of Dyers and Colorists, 28,

have found a marked difierentiation between those monium hydroxide,

'when the run is under guanidines, such as guanidine,;monomethylguanidine, dimethyl guanidine and butyl guanidine, even up to concentrations of appear to have very little swelling or mercerizingaction and no increase in the strength of cotton yarns can be 5 detected when run under conditions identical with those run with sodium hydroxide.

In our co-pending application, Serial No. 676,530, Patent No. 2,009,015, dated July 23, 1935, we have shown that quaternary ammonium bases 1 of relatively high molecular weight, notably those containing a benzyl group, are unique and striking in their action on; cellulose.- We rind that these benzyl substituted ammonium hydroxides in concentrated aqueous solution effect a rapid 15 and substantially complete solution of cellulose materials. We have also found that more dilute solutions. of benzyl substituted ammonium hydroxides are not rapid solvents for cellulose, but are active swelling and mercerizing agents. 20 When a 42% solution of dimethylbenzylphenylammonium hydroxide is diluted with an equal weight of water to a 21% solution, it loses its action as a rapid solvent and becomes 'a powerful swelling or mercerizing agent. These 25 dilute solutions of quaternary bases may be used as mercerizing agents and yield products of high luster andstrength.

- We also flnd that the addition of small amounts of benzyl substituted ammonium hydroxides to so mercerizing solutions of sodium hydroxide markedly improves their penetrat'on of cotton yarns and the resulting material has an improved luster and feel. r i

We findthat dilute solutions of benzyl sub- 35 sti tuted. quaternary ammonium hydroxides are more efiective mercerizing agents than solutions of other organic bases such as tetramethylamguanidine or methyl guanidine, etc. A 25% solution of trimethylbenzylam- 41 monium hydroxide gives a 33% increase in tensile strength when mercerization is carried out for 5 minutes at 0 C. A.20% solution of sodium hydroxide shows an increase in strength of only 16% similar, carefully con- 4 trolled conditions. I

We find that when cellulose material such as cotton sheeting is run into a dilute solution of a benzyl substituted ammonium. hydroxide and dried by running through a stream of hot air 5 or passing over dry cans, the quaternary ammonium'hydroxide concentrates in the material effecting a gelatinization of the fiber, giving a perma 'ent finish-{on calendering which is fast towasllinl'v- 12" j ton.grey goods appears fpyridonium hydroxide.

The action of dilute caustic solutions on cotto be improved by the addition of a benzyl substituted ammonium hydroxide with or without the presence of soap.

, We find, for example, that when a small amount where R, R R are alkyL'aryl and aralkyl groups or substituted derivatives thereof.

Among the benzyl substituted quatemary ammonium hydroxides which have been found to be suitable are; trimethylbenzylammonium hydroxide, triethylbenzylammonium hydroxide. dimethylphenylbenzylammonium hydroxide, di-

ethylphenylbenzylammoniiim hydroxide, dimethyltolylbenzylammonium hydroxide, dimethylamylbenzylammonium hydroxide, di-

methyldibenzylammonium hydroxide and benzyl It is clear to anyone skilled in the art that other benzyl substituted quaternary ammonium hydroxides would also be effective; for example, the methyl groups in-trimethylbenzylammonium hydroxide may be replaced by other albl groups in a product such as dimethylbenzylphenylammonium hydroxide .might be replaced by tolyl, xylyl or 'naphthyl groups. amples will serve to illustrate our invention:

(1) Cotton yarn was rim through a mercerizing bath containing a 1.5 normal solution of trimethylbenzylammoninm hydroxide. The yarn was wet with this solution for 3 minutes under tension. This yarn was then given a water wash, a thorough soaping, rinsed and dried. It proved to have 35% greater tensile'strength than the untreated yarn and possessed a. good luster.

(2) Cotton sheeting was run into a 30% solution of dimethylbenzylphenylammonium hydroxide and piledin boxes and allowed to stand for 3to5minutes. Attheendofthistimeitwas run directly into an open tub, given a thorough water wash which was followed by a boiling soap. The resulting fabric, on calendaring, had a high luster and a rayon-like appearance.

(3) Cotton broadcloth was run through {10% ldibenzylammonium solution of dime The following exide. The impregnated fabric was then passed through a hot air drier or hot air heated tenter frame. l bllowing this treatment the fabric was rim into a dilute acid solution followed by a rinsing with a solution containing to t of 1% of sodium lauryl sulphate. A permanent finish is obtained which is not readily removed by repeated washings.

(4) A rayon alpaca was run through an 8% solution of triethylbenzylammonium hydroxide at room temperature and given a tight squeeze before through a battery of rotating dry cans heated with warm air. The fabric was then run into a boiling soap solution, rinsed, dried and given a friction calender to produce a finish resembling a linen fabric.

(5) Cotton broadcloth was mercerized in the usual manner on a mereerizing frame at room temperature with a 20% solution of sodium hydroxide containing 1% trimethylbenzylammonium hvdroxide. Good mercerization was obtained in 3 minutes and the goods were run into cold water followed by an immersion in 3% sulphuric acid. They were then washed in water'and dried.

It will be recognized by one versed in the art that deyiation can be made in the above examples without departing from the spirit of the invention, the scope of which is limited only by the following claims.

What we. claim is;

1. A process of mercerizing which comprises treating cellulose bodies with a dilute aqueous solution ofa quaternary benzyl ammonium hyr e. such as propyl, butyl, etc; and a phenyl group Y dmxid 2. A process of mercerizing which comprises treating cellulose bodies with a dilute solution of a compound of the general formula where R, R R are alkyl, aryl, and aralkyl cellulose bodies with av solution of a comprises treating cellulosic bodies with a solution contaming a quaternary benzyl ammonium hydrox'; ide. a

DONALD E. LOUISEBOCK. I 

